Being Afraid Of The Dark Is Ruining My Life

I am 44, living with my partner & 2 teenage sons, my fear of the dark is worse now than ever. My partner works away a lot of the time, my one son has joined the army so he only comes home on leave & my other son is always out or at his girlfriends house. This means I am at home alone a lot of the time. I have always been afraid of the dark but know its taking over to the point I want my partner to look for a new job & I try to bribe my son to stay home. I know my fear is totally irrational but it does not stop me. When I am home alone all the lights in the house are on, I sleep with my mobile phone, my iPad ,a knife & a hammer on the bed with me. The tv is on all night & my sleep is very limited as I just drift in & out of sleep & I fight it every step of the way. My partner is very god but I honestly don't think he fully understands how I feel. My sons just think kits amusing & I am usually the but of there jokes. I know I really need help but don't know where to start. I would be grateful for any input from anyone.